Effects of irradiation and extrusion on starch and protein in sorghum and rapeseed performance in Cobb broiler chicks

摘要

2017.. Sorghum and rapeseed meal were subjected to electron beam irradiation at a dose of 20 kGy and/or extruded at 145 °C for 15 seconds. Chemical composition and morphology was determined by SDS-PAGE, electron microscopy and X diffraction. Irradiated, extruded sorghum, rapeseed and Cobb feed controls were given to groups of 25 Cobb broiler chicks each for 42 days with free access to feed and water. Feed intake, body weight and feed conversion ratios were recorded at 21 and 42d. Irradiation nor extrusion affected chemical composition, but did reduce tannins and phenols in sorghum and rapeseed meal. Extrusion reduced molecular weight of protein subunits further than irradiation whereas irradiation reduced the crystal structure of starch further than extrusion. Electron microscopy confirmed the results. Irradiation and extrusion of feed increased daily weight gain and improved feed conversion ratio compared with controls.